This invention relates to a medical diagnostic ultrasound system and method for identifying constrictions. In particular, regions of little or no flow in a vessel due to constrictions of the vessel are distinguished from artifact signal dropout that wrongly suggests little or no flow.
Accurate diagnosis of constrictions in blood vessels, such as the carotid, assists medical treatment. Three-dimensional ultrasound images of the carotid are rendered from blood flow information. The rendered images show arterial constrictions in the carotid. The geometry of the rendering is examined for any constriction. Since imaging artifact signals may also result in an apparent constriction where no or a smaller constriction exists, human judgement is required to determine whether the shown constriction is attributable to an actual constriction or signal artifact. This subjective technique is prone to error.
The present invention is defined by the following claims, and nothing in this section should be taken as a limitation on those claims. By way of introduction, the preferred embodiment described below includes a method and system for identifying constrictions in a vessel. Total blood volume flow is measured at various points along the vessel. The total volume flow is conserved. Regions with a different volume flow than expected (e.g. areas associated with a lower volume that violates the conservation of flow principle) are identified as suspicious. Suspicious regions are likely associated with a dropout artifact. Actual constrictions are determined from the geometry of images where the region is not suspicious.
In one aspect, a medical diagnostic ultrasound method for identifying a constriction in a vessel with an ultrasound system is provided. Volume fluid flow within the vessel is measured. An image of a portion of the vessel is generated.
An artifact is indicated in the image in response to the volume fluid flow measurement. In another aspect, a constriction in the image is indicated as a function of the volume fluid flow measurement.
Further aspects and advantages of the invention are discussed below in conjunction with the preferred embodiments.